As a co-worker, but of such a mentality and personality as to be almost entirely indistinguishable from a smartly-dressed cow. The differences between a cow-worker and a cow should, however, be obvious on closer examination. One is a large, mindless animal that grazes off scraps of food matter, travels in herds, and is primarily of value only because it can be eventually disposed of for the betterment of a large group of people. The other gives us milk.

"Gary, do you have that report done I asked you for this morning?"
"Moo."
"Okay, one more day, but after that you're answering to the boss yourself."
"Moo."
"You'd better hurry. We're on a tight clock."
"Moo."
"Thanks.... God, I hate my cow-workers."